Water pumping and control system



Feb. 17, 1970 w. c. MORELAND 1|, ETAL 3,495,612

WATER PUMPING AND CONTROL SYSTEM Filed Sept. 28, 1967 PUMP COMPRESSOR IB/ 4o FIG.3 i

WITNESSES: INVENTORS WIIIIGm C. Morelund, III a Y Leland L. Learn Man MW g I BY United States Patent O U.S. Cl. 137209 8 Claims ABSTRACT OF THE DISCLOSURE Bottled supply water cooler apparatus in which the supply bottle is located below a cooling chamber and in which the water is forced from the supply bottle up to the cooling chamber by a pumping system which draws air until the desired water level is reached in the cooling chamber and then recirculates the last supplied water at a reduced rate.

BACKGROUND OF THE INVENTION Field of the invention The field of art to which the invention pertains is generally that of water coolers using a bottled water supply, and in particular to a water cooler in which the bottled water supply is located in the lower part of the water cooler with the water being pumped to a higher cooling chamber.

Description of the prior art The concept of pumping water to a dispensing reservoir (usually a cooling chamber) located at a higher level than the bottled water supply in such units, is not new as evidenced by US. patents as 3,269,143; 3,179,292; 3,141,- 573; and 3,244,329, for example. The present invention deals with the general subject of a water cooler which, in common with the arrangements in the noted patents, uses a pumping system to elevate water from the lower bottled supply, but which is .considered to have a superior pumping and control system.

SUMMARY OF THE INVENTION The gist of the invention in one of its aspects is the provision of a pumping system in which the suction side of the pump normally draws air from the dispensing reservoir until the desired level of water is reached in the dispensing reservoir, at which time water is drawn into the pump. Further, the inlet end of the suction conduit is closely coupled to the outlet of the supply conduit through which water is elevated from the supply water bottle in a space in the dispensing reservoir in restricted communication with the space in the remainder of the dispensing reservoir. Hence, the recirculation of water from the dispensing reservoir is substantially restricted to the last-in water from the supply bottle, which water has not been cooled to any substantial extent.

Further in accordance with the invention, the pump is of the character having a substantially lower volumetric fiow rate when pumping water than when pumping air so that the recirculation rate is substantially reduced relative to the recovery rate. To further reduce the recirculation rate, it is preferred that the suction conduit have an interior diameter which is substantially less than the interior diameter of the supply conduit through which water is pumped from the bottle to the dispensing reservoir.

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DRAWING DESCRIPTION type of valve for closing the suction conduit end in one alternative arrangement of the invention; and

FIG. 3 is an electrical schematic view of another arrangement for controlling the water cooler operation.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The apparatus shown in FIG. 1 includes an outer cabi net 10 having a space in its lower portion to receive the removable liquid reservoir which is typically in the form of the water bottle 12 of the type commercially available. The dispensing reservoir 14, which is illustrated as being of the cooling chamber type, is located in the upper portion of the cabinet and is provided with an outlet spigot 16.

The pumping and control system includes the pump 18 having its pressure side connected by pressure conduit 20 to the interior of the bottle 12. The bottle top is sealed by a stopper 22 through which the pressure conduit 20 and the water supply conduit 24 extend. A suction conduit 26 extends from the suction side of the pump 18 up to the interior of the dispensing reservoir 14 where its inlet end 28 may be seen to be disposed in the upper portion of the reservoir 14. It may also be seen from FIGS. 1 and 2 that the outlet end 30 of the water supply conduit 24 is closely coupled, i.e., closely adjacent, to the inlet end of the suction conduit. The small space 32 in the reservoir within which these ends 28 and 30 are located is in restricted communication with the larger remaining space 34 in the reservoir. This separation of spaces 32 and 34 may be simply eifected by the provision of an open bottomed partition 36.

It is contemplated that in the normal application of the invention the dispensing reservoir 14 will be refrigerated by cooling coils 38 connected to the diagrammatically illustrated refrigerant compressor 40, refrigerant condenser 42 and associated connecting tubes. While the pumping and control system is not restricted to use with rerigerated systems, its more useful application is found in such a system.

The currently preferred pump 18 for application to the subject invention is of the general character disclosed in US. Patent 3,212,446 but modified slightly to adapt its suction and pressure ports for connection to conduits, rather than having either one open to the atmosphere about the pump. Such a vibrating tuned pump has a substantially lower volumetric flow rate when pumping water than when pumping air. Accordingly, after the water level in the dispensing reservoir 14 has been elevated to a level at which the end 28 of the suction conduit 26 is immersed, continued operation of the pump 18 will draw water from the space 32 (rather than air from the space) but at a substantially reduced volumetric flow rate.

The continued pumping of water at the reduced rate results in a recirculation of the water throughout the entire system including the bottle 12 and the reservoir 14 but without a further net transfer of water from the bottle to the reservoir. Therefore, the desired level in the reservoir is maintained even though the pump continues to run. In a refrigerated system, the recirculation of water between the reservoir and bottle increases the thermal load on the compressor and accordingly it is desirable to reduce the recirculation rate without greatly affecting the recovery rate. A further reduction in the volumetric flow rate when water is being circulated may be obtained by using a suction conduit 26 providing greater resistance to flow than the supply conduit 24. One convenient Way of accomplishing this is to use a smaller suction conduit than supply conduit which has also been found to reduce air noise to a relatively low level.

Additionally, a reasonably large suply conduit should be used so that air is not excessively compressed in the bottle 12. Otherwise a net pumping will continue even after the pump is stopped due to the dynamic pressure drop in the tube requiring a higher pressure in the bottle than the static head requirement of the lift. When the bottle is very low in water and thus has a large volume of compressed air, this could be sufficient to overfill the reservoir and cause water to spill out of the reservoir.

The manner of operation of the system is as follows. Energization of the pump 18 forces air through the conduit 20 to pressurize the interior of the bottle 12 and force the water from the bottle up through the supply conduit 24 for discharge into the reservoir 14. When the level of the water in the reservoir reaches a level immersing the end 28 of the suction conduit, the suction conduit begins to draw water, rather than air, from the space 32, without a net exchange of water between bottle and reservoir. This automatically reduces the volumetric fiow rate substantially, especially if the suction conduit provides greater restriction to flow than the supply conduit.

In most applications it will not be desirable to have the pump 18 running continuously. The control of the pump 18 in accordance with the level of water in the reservoir 14 may be accomplished in various ways. One convenient way is to provide a float 44 (FIG. 2) in the dispensing reservoir which operates a switch to terminate operation of the pump 18 at the desired upper level of water in the reservoir. A float may also carry a sealing element 46 for the inlet end 28 of the suction conduit where positive prevention of recirculation of Water from a cooling reservoir back to the supply bottle 12 is desired. The partition means 36 of course restricts communication between the inlet space 32 and the remaining space 34 in the dispensing reservoir so that even if recirculation from the reservoir does occur for some reason, purposely or otherwise, most of the water recirculated and drawn into the suction conduit 26 will be that which has been just discharged from the end 30 of the supply conduit.

In another arrangement for control as shown in FIG. .3, a temperature sensing element 48 located at about the desired high water level in the reservoir controls both the pump 18 and refrigerant compressor 40 which are connected in parallel for joint control by switch 50 actuated by diaphragm 52. When an appreciable amount of water is withdrawn from the reservoir, the reduced thermal mass causes both pump and compressor to operate to bring the water level back up and cool the water. If the full reservoir requires cooling only the operation of the pump as well is of little significance since recirculation occurs. This arrangement is one example of the usefulness of the recirculation aspect of the invention since it eliminates a separate water level control switch. However, even where it is preferable to stop the pump operation when the desired water level is reached, the disclosed recirculating system is useful as a safety backup system, and avoids a requirement that the pump switch be critically adjusted.

What is claimed is:

1. A pumping system for water dispensing apparatus including:

an unsealed dispensing reservoir from which water is dispensed from time to time;

a supply reservoir of water located at a level below said dispensing reservoir;

a pump having a suction inlet and a pressure outlet;

a pressure conduit connecting said pressure outlet to the interior of said supply reservoir;

a liquid supply conduit connecting the interior of said supply reservoir with said dispensing reservoir;

a suction conduit connecting said suction inlet to a level in the interior of said dispensing reservoir approximating the desired water level in said dispensing reservoir, so that during pumping said suction conduit draws air until the water level in said dispensing reservoir reaches the level of said suction conduit and said suction conduit then draws water to prevent an overfill condition of said dispensing reservoir by recirculating water from said dispensing reservoir to said supply reservoir; and

said pump, said conduits and said reservoirs being open to atmosphere only through said dispensing reservoir so that said recirculation of water does not result in any Water loss.

2. A system according to claim 1 wherein:

said suction conduit provides greater resistance to flow than said supply conduit.

3. A system according to claim 1 wherein:

said pump is of the character having a substantially lower volumetric flow rate when pumping water than when pumping air.

4. A system according to claim 2 wherein:

said pump is of the character having a substantially lower volumetric flow rate when pumping water than when pumping air.

5. A system according to claim 1 wherein:

the ends of said suction conduit and said supply conduit in said dispensing reservoir are closely adjacent each other; and

said dispensing reservoir includes means for restricting communication between a first space in said dispensing reservoir adjacent said conduit ends and the remaining water-occupied space to promote recirculation of water from said first space.

6. A water supply and dispensing apparatus comprising:

an outer cabinet;

a removable liquid reservoir in the lower portion of said cabinet;

an independent liquid dispensing reservoir in an upper portion of said cabinet;

pump means for forcing liquid from said lower reservoir to said dispensing reservoir;

a suction conduit having one end in communication with the upper portion of said dispensing reservoir and the other end connected to the inlet of said pump means;

a pressure conduit extending from the outlet of said pump means to the interior of said removable liquid reservoir;

a supply conduit extending from said removable liquid reservoir to said upper portion of said dispensing reservoir and having its outlet closely adjacent the inlet of said suction conduit; and

means restricting communication between the space in said dispensing reservoir adjacent the ends of said supply and suction conduits, and the remainder of the space subject being occupied by water in said dispensing reservoir.

7. Apparatus according to claim 6 wherein:

said suction conduit is cross-sectionally smaller than said supply conduit;

the ends of said suction conduit and said supply conduit in said dispensing reservoir are closely adjacent; and

means reflecting the level of water in said dispensing reservoir for controlling the operation of said pump.

5 6 8. Awater cooler includinga References Cited a lower water supply reservoir; UNITED STATES PATENTS an upper Water coollng chamber; a refrigerating system for said chamber; 2,021,394 11/1935 Wade 5 X a pumping system of the type forcing water from said 2,854,326 10/ 195 8 Johnston 6255 reservoir to said chamber and recirculating water from said chamber back to said reservoir when a selected level in said chamber is reached; and U S Cl R means disposed to respond to variations in Water temperature in the vicinity of said selected level for 62-494; 137--563;222--130, 394

controlling operation of both said pumping system and said refrigerating system.

ALAN COHEN, Primary Examiner 

